The two fundamental challenges in compensating for lack of vision are reading and getting from one place to another. Reading of books has been mitigated by OCR (optical character recognition), and screen readers have provided access to computers and the internet. Getting around is a different story, with two separate components, obstacle detection and accessing location information.

I have been focusing on accessible location information with GPS since 1993 and more recently working on indoor navigation. Four accessible GPS systems are now on the market; however, indoor options are primarily still in the research stage.

The Miniguide, Ultra Cane, Laser Cane and Kay-Sonar are the latest in obstacle detection devices. The blind community maintains that the dog and cane provide adequate guidance and that there is no need for obstacle detection unless it enables access to driving or cycling. The future holds the possibility of seamless indoor/outdoor navigation and integration with obstacle detection on a Segway or perhaps even in a semi-autonomous vehicle.